Dutch bills that could curtail the freedom of movement of terrorist suspects and strip them of their Dutch citizenship for joining terrorist organizations may violate human rights, the Council of Europe said, while asking the Netherlands for clarification.

In a letter to the Dutch government, the Council of Europe’s commissioner for human rights, Nils Muiznieks, expressed concern about three legislative proposals passed this year by Holland’s lower house parliament, the Tweede Kamer, warning that they may violate international human rights treaties.

Included in the legislation under scrutiny is the Temporary Administrative Measures Bill, which would allow restrictions to be placed on a suspect’s freedom of movement and private and family life, the Council wrote in a statement.

In the letter, Muiznieks wrote that he is concerned that the bill directly undermines the “rights enshrined in the European Convention on Human Rights (ECHR),” noting that it includes restrictions that could require a person to report to the authorities or “ban a person’s presence in certain areas or near certain objects.”

The bill would ban individuals thought to be connected with terrorist activities from traveling abroad, and Muiznieks is worried that such restrictions could be imposed based solely on a person’s behavior.

Noting that the wording of the bill is “open to a very expansive interpretation,” he asked the Dutch authorities to explain “how this provision is or can be brought in line with the aforementioned ECHR standards.”

Muiznieks went on to express concern about the Nationality Act, which would allow dual nationals to be stripped of their Dutch citizenship if it is apparent that they pose a threat to national security or have joined an organization that the government deems to be party to an internal or international conflict. A minister could revoke a suspect’s citizenship without needing to go to court if the bill becomes law.

The commissioner stated that such revocations must not be allowed to “unduly affect religious or ethnic groups and social cohesion” and be accompanied by an “effective remedy.” He also asked for clarification of some of the vague language contained in the bill.

Lastly, the bill would expand the authorities’ power to conduct blanket online surveillance on large groups, which could affect individuals that are in no way connected to crimes or activities endangering national security. Muiznieks noted that, with such overarching authority, “strong oversight is crucial,” given the “expansive natures of the powers involved.”

While acknowledging that terrorism is a genuine threat, the commissioner insisted that repressive measures are not the answer.

“Prevention is key. Governments have the duty to ensure that their responses to terrorism uphold human rights standards and are accompanied by systematic, inter-religious and cross-cultural dialogue fostering a cohesive society,” he wrote.

The Tweede Kamer has defended the bills, however, with CDA parliamentarian Madeleine van Toorenburg telling Algemeen Dagblad that “all the arguments that the Council brings, we also considered.”

“The reason why we are not taking away the passport of every terrorist is precisely because we want to adhere to international conventions: people must not be stateless,” she said.

Both bills must still be passed by the Eerste Kamer, the Dutch Senate, to become law.